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Bob The Builder
From Unmariowiki
Bob The Builder is a builder. He appears in the Marioverse many times. The first time was in the original Super Mario Bros. and he apeared as a boss. When Mario defeated Bowser, Bob The Builder arose from the lava, and mario had to challenge this beast. He is weak to building. He appears again in Paper Luigi, as a boss of fix-it-up castle. His final appearance was in New Super Mario Bros. where Mario defeated him.
In an interview for the one who thought of the idea for Bob, he said that "I don't think Bob will appear again. After all the Mario series will end soon," he said. However note that Bob the Builder got his own TV series, however Mario is never mentioned or seen.